1. Field of the Invention
The present invention relates to metal roofing on buildings, and more particularly to a new roof curb system and method of installation.
2. Description of the Prior Art
Metal buildings having metal roofing have become popular for commercial, industrial and warehousing uses. Such buildings often require roof openings for such equipment as skylights, fans, air conditioning units, and the like. The installation of such equipment requires a roof curb unit for support.
Roof curb systems are well known in the art. U.S. Pat. No. 4,559,753 describes a method of installation of a metal roof curb unit in which the rims of the curbs are pre-welded to a roof panel, and the curb containing-panel is attached to a large opening cut into the roof. However, this method requires cutting a hole in the roof that is much larger than the opening for the equipment, and it is highly susceptible to leakage.
Other patents describe single or multi-sided roof curbs such as U.S. Pat. Nos. 4,917,345, 5,016,406, 5,148,647 and 5,465,533 which describe adjustable and/or interlocking roof curbs.
The following U.S. Patents are also known to exist:
______________________________________ U.S. Pat. No. Issue Date Inventor ______________________________________ 4,413,450 November 8, 1983 Brower 4,887,399 December 19, 1989 Berger DES 217,223 April 21, 1970 Knohl DES 221,941 September 21, 1971 Murphy DES 387,442 December 9, 1997 Toovey DES 391,648 March 3, 1998 Solbeck ______________________________________